1. Field of the Invention
The invention relates to a touch pen for a computerized apparatus, more particularly to a touch pen with an illuminating unit.
2. Description of the Related Art
Portable computerized apparatuses, such as personal digital assistants, have grown in popularity in recent years. In an example of a known personal digital assistant, a transparent touch control panel, which serves as a user input unit, can be pressed at a specific location by a touch pen so as to generate a control signal corresponding to the specific location. A back lighting unit, which serves as an illumination unit, is used to provide illumination for the personal digital assistant when the latter is used in a dim environment. Usually, a rechargeable battery set supplies power to the personal digital assistant. The fully-charged battery set has a service life of about 15xcx9c16 hours in normal use without activating the back lighting unit. However, the fully-charged battery has a shorter service life of about 2 hours when the back lighting unit is constantly activated. Accordingly, power consumption of the personal digital assistant is increased when the back lighting unit is activated such that the battery set has a shorter service life, thereby resulting in inconvenience during use.
Therefore, the object of the present invention is to provide a touch pen with an illuminating unit that can be used to operate a computerized apparatus in a dim environment without activating a back lighting unit of the computerized apparatus.
According to the present invention, a touch pen is adapted for use with a computerized apparatus having a touch control panel, and comprises:
a pen barrel having first and second barrel portions opposite to each other along an axis of the pen barrel, the first barrel portion being formed with an open end;
an illuminating unit received in the first barrel portion, and including a light source, a power source, and a switch connected to the light source and the power source and operable so as to establish electrical connection between the light source and the power source for enabling the light source to generate a light output which radiates out of the pen barrel via the open end of the first barrel portion; and
a transparent pen cap having a mounting end portion sleeved removably on the first barrel portion, and a touch tip opposite to the mounting end portion and adapted for touching the touch control panel of the computerized apparatus.